2-Butyn-1-ol, 4-((tetrahydro-1,1-dioxido-3-thienyl)oxy)- 4-((Tetrahydro-3-thienyl)oxy)but-2-yn-1-ol S,S-dioxide 40456-28-8 EINECS 254-927-2 Hydroxybutyne 3-sulfolanyl ether